a = int(input())
b = int(input())
c = int(input())
a2 = a*a
b2 = b*b
c2 = c*c

if a >= b+c or b >= a+c or c >= a+b:
    print('not a triangle')
elif a2 == b2+c2 or b2 == a2 + c2 or c2 == a2+b2:
    print('yes')
else:
    print('no')
